04-3354. Airworthiness Directives; BURKHARDT GROB LUFT-UND RAUMFAHRT GmbH & CO KG Models G103 Twin ASTIR, G103 Twin II, G103 Twin III ACRO, and G103 C Twin III SL Sailplanes

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

The FAA proposes to adopt a new airworthiness directive (AD) for certain BURKHARDT GROB LUFT-UND RAUMFAHRT GmbH & CO KG (Grob) Models G103 Twin ASTIR, G103 Twin II, G103 Twin III ACRO, and G103 C Twin III SL sailplanes. This proposed AD would require you to replace the center of gravity (CG) release hook attachment brackets with brackets of improved design. This proposed AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Germany. We are issuing this proposed AD to prevent abnormal or uncontrolled sailplane release due to cracked CG release hook attachment brackets. This condition could result in reduced or loss of sailplane control.

DATES:

We must receive any comments on this proposed AD by March 29, 2004.

ADDRESSES:

Use one of the following to submit comments on this proposed AD:

• By mail: FAA, Central Region, Office of the Regional Counsel, Attention: Rules Docket No. 2003-CE-61-AD, 901 Locust, Room 506, Kansas City, Missouri 64106.
• By fax: [phone].
• By e-mail: [e-mail]. Comments sent electronically must contain “Docket No. 2003-CE-61-AD” in the subject line. If you send comments electronically as attached electronic files, the files must be formatted in Microsoft Word 97 for Windows or ASCII.

You may get the service information identified in this proposed AD from BURKHARDT GROB LUFT-UND RAUMFAHRT GmbH & CO KG, Letenbachstrasse 9, D-86874 Tussenhausen-Mattsies, Germany; telephone: [phone]; facsimile: 011 49 8268 998200.

You may view the AD docket at FAA, Central Region, Office of the Regional Counsel, Attention: Rules Docket No. 2003-CE-61-AD, 901 Locust, Room 506, Kansas City, Missouri 64106. Office hours are 8 a.m. to 4 p.m., Monday through Friday, except Federal holidays.

FOR FURTHER INFORMATION CONTACT:

Greg Davison, Aerospace Engineer, FAA, Small Airplane Directorate, 901 Locust, Room 301, Kansas City, Missouri 64106; telephone: [phone]; facsimile: [phone].

SUPPLEMENTARY INFORMATION:

Comments Invited

How do I comment on this proposed AD? We invite you to submit any written relevant data, views, or arguments regarding this proposal. Send your comments to an address listed under ADDRESSES. Include “AD Docket No. 2003-CE-61-AD” in the subject line of your comments. If you want us to acknowledge receipt of your mailed comments, send us a self-addressed, stamped postcard with the docket number written on it. We will date-stamp your postcard and mail it back to you.

Are there any specific portions of this proposed AD I should pay attention to? We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this proposed AD. If you contact us through a nonwritten communication and that contact relates to a substantive part of this proposed AD, we will summarize the contact and place the summary in the docket. We will consider all comments received by the closing date and may amend this proposed AD in light of those comments and contacts.

Discussion

What events have caused this proposed AD? The Luftfahrt-Bundesamt (LBA), which is the airworthiness authority for Germany, recently notified FAA that an unsafe condition may exist on certain Grob Models G103 Twin ASTIR, G103 Twin II, G103 Twin III ACRO, and G103 C Twin III SL sailplanes. The LBA reports incidents of cracks found in the center of gravity (CG) release hook attachment brackets.

Grob has manufactured new improved design CG release hook attachment brackets that are less susceptible to such cracking.

What are the consequences if the condition is not corrected? A cracked CG release hook attachment bracket, if not prevented, could lead to abnormal or uncontrolled sailplane release. This condition could result in reduced or loss of sailplane control.

Is there service information that applies to this subject? Grob has issued Service Bulletin No. MSB869-22, dated January 22, 2002, and Service Bulletin No. MSB315-62, dated January 21, 2002. The service bulletins include procedures for inspecting and replacing the CG release hook attachment brackets.

What action did the LBA take? The LBA classified these service bulletins as mandatory and issued the following to ensure the continued airworthiness of these sailplanes in Germany:

• German AD No. 2002-066, effective date: March 21, 2002; and
• German AD No. 2002-067, effective date: March 21, 2002.

Did the LBA inform the United States under the bilateral airworthiness agreement? These Grob Models G103 Twin ASTIR, G103 Twin II, G103 Twin III ACRO, and G103 C Twin III SL sailplanes are manufactured in Germany and are type-certificated for operation in the United States under the provisions of section 21.29 of the Federal Aviation Regulations (14 CFR 21.29) and the applicable bilateral airworthiness agreement.

Under this bilateral airworthiness agreement, the LBA has kept us informed of the situation described above.

FAA's Determination and Requirements of This Proposed AD

What has FAA decided? We have examined the LBA's findings, reviewed all available information, and determined that AD action is necessary for products of this type design that are certificated for operation in the United States.

Since the unsafe condition described previously is likely to exist or develop on other Grob Models G103 Twin ASTIR, G103 Twin II, G103 Twin III ACRO, and G103 C Twin III SL sailplanes of the same type design that are registered in the United States, we are proposing AD action to prevent abnormal or uncontrolled sailplane release due to cracked CG release hook attachment brackets. This condition could result in reduced or loss of sailplane control.

What would this proposed AD require? This proposed AD would require you to replace the CG release hook attachment brackets with brackets of improved design.

How does the revision to 14 CFR part 39 affect this proposed AD? On July 10, 2002, we published a new version of 14 CFR part 39 (67 FR 47997, July 22, 2002), which governs FAA's AD system. This regulation now includes material that relates to altered products, special flight permits, and alternative methods of compliance. This material previously was included in each individual AD. Since this material is included in 14 CFR part 39, we will not include it in future AD actions.

Costs of Compliance

How many sailplanes would this proposed AD impact? We estimate that this proposed AD affects 105 sailplanes in the U.S. registry.

What would be the cost impact of this proposed AD on owners/operators of the affected sailplanes? We estimate the following costs to do this proposed replacement:

Labor cost	Parts cost	Total cost per sailplane	Total cost on U.S. operators
2 workhours at $65 per hour = $130	$50 per sailplane	$180 per sailplane	$18,900

Regulatory Findings

Would this proposed AD impact various entities? We have determined that this proposed AD would not have federalism implications under Executive Order 13132. This proposed AD would not have a substantial direct effect on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government.

Would this proposed AD involve a significant rule or regulatory action? For the reasons discussed above, I certify that this proposed AD:

1. Is not a “significant regulatory action” under Executive Order 12866;

2. Is not a “significant rule” under the DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and

3. Will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act.

We prepared a summary of the costs to comply with this proposed AD and placed it in the AD Docket. You may get a copy of this summary by sending a request to us at the address listed under ADDRESSES. Include “AD Docket No. 2003-CE-61-AD” in your request.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Safety

The Proposed Amendment

Accordingly, under the authority delegated to me by the Administrator, the Federal Aviation Administration proposes to amend 14 CFR part 39 as follows:

PART 39—AIRWORTHINESS DIRECTIVES

1. The authority citation for part 39 continues to read as follows:

Authority: 49 U.S.C. 106(g), 40113, 44701.

§ 39.13

[Amended]

2. The FAA amends § 39.13 by adding the following new airworthiness directive (AD):

BURKHARDT GROB LUFT-UND RAUMFAHRT GmbH & CO KG: Docket No. 2003-CE-61-AD.

When Is the Last Date I Can Submit Comments on This Proposed AD?

(a) We must receive comments on this proposed airworthiness directive (AD) by March 29, 2004.

What Other ADs Are Affected by This Action?

(b) None.

What Sailplanes Are Affected by This AD?

(c) This AD affects the following model and serial number sailplanes that are certificated in any category:

Models	Serial numbers
(1) G103 Twin ASTIR	3000 through 3291.
(2) G103 Twin II	3501 through 3720.
(3) G103 Twin III ACRO	All serial numbers beginning with 34101.
(4) G103 C Twin III SL	35002 through 35051.

What Is the Unsafe Condition Presented in This AD?

(d) This AD is the result of is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Germany. The actions of this AD are intended to prevent abnormal or uncontrolled sailplane release due to cracked center of gravity (CG) release hook attachment brackets. This condition could result in reduced or loss of sailplane control.

What Must I Do To Address This Problem?

(e) To address this problem, you must do the following:

Actions	Compliance	Procedures
(1) Replace the CG release hook attachment brackets with improved design brackets, as follows: (i) For the Models G103 Twin ASTIR, G103 Twin II, and G103 Twin III ACRO sailplanes: part number (P/N) 103B-2360.01/1 and P/N 103B-2360.02/1; and (ii) For the Model G103 C Twin III SL sailplane: P/N 103B-2360.01/2 and P/N 103B-2360.02/2.	Within the next 25 hours time-in-service (TIS) after the effective date of this AD, unless already done	Follow Grob Service Bulletin No. MSB869-22, dated January 22, 2002; and Grob Service Bulletin No. MSB315-62, dated January 21, 2002.
(2) Do not install any CG release hook attachment bracket that is not a part number referenced in paragraphs (e)(1)(i) and (e)(1)(ii) of this AD, as applicable	As of the effective date of this AD	Not applicable.

May I Request an Alternative Method of Compliance?

(f) You may request a different method of compliance or a different compliance time for this AD by following the procedures in 14 CFR 39.19. Unless FAA authorizes otherwise, send your request to your principal inspector. The principal inspector may add comments and will send your request to the Manager, Standards Office, Small Airplane Directorate, FAA. For information on any already approved alternative methods of compliance, contact Greg Davison, Aerospace Engineer, FAA, Small Airplane Directorate, 901 Locust, Room 301, Kansas City, Missouri 64106; telephone: [phone]; facsimile: [phone].

May I Get Copies of the Documents Referenced in This AD?

(g) You may get copies of the documents referenced in this AD from BURKHARDT GROB LUFT-UND RAUMFAHRT GmbH & CO KG, Letenbachstrasse 9, D-86874 Tussenhausen-Mattsies, Germany; telephone: [phone]; facsimile: 011 49 8268 998200. You may view these documents at FAA, Central Region, Office of the Regional Counsel, 901 Locust, Room 506, Kansas City, Missouri 64106.

Is There Other Information That Relates to This Subject?

(h) German AD No. 2002-066, effective date: March 21, 2002; and German AD No. 2002-067, effective date: March 21, 2002, also address the subject of this AD.

Issued in Kansas City, Missouri, on February 10, 2004.

James E. Jackson,

Acting Manager, Small Airplane Directorate, Aircraft Certification Service.